In the 1992 presidential election, Perot ran as a candidate of the
"United We Stand America" party with the hapless Admiral James Stockdale as his running-mate. He actually quit the presidential race
at one point, only to rejoin several months later--a move that saved him
money but made him vulnerable to the charge that he was just as much of
a waffle as George Bush and Bill Clinton. Unlike Ralph Nader,
Perot was allowed to participate in the debates. Overall, the
effect was
mixed--some felt that he handled himself quite well (and garnered some
nice prime-time TV publicity to boot); others decided not to vote for him,
feeling that the man had revealed himself to be a certifiable gabbling
lunatic. Nonetheless, he did quite well overall, winning 18% of the
vote and actually coming in second in a few states.

Perot ran as a Reform Party candidate in 1996, but didn't do as well; he wasn't allowed in the debates and ultimately got 9% of the vote.

Even though Perot didn't win, he showed that third-party candidates
could get enough votes to swing an election--and that,
consequently, the major parties should adopt the ideas of strong third
parties or risk losing those votes and therefore the election. Thus, third-party voters can "win" in a sense, even if their candidate loses. (For example, nobody cared much about balancing the budget until Perot made it a national issue; then you heard about it much more often).

(A brief aside: Perot was one of the single most bizarre men ever to
run for President in the TV era. Comedy shows like Saturday Night
Live could reduce audiences to tears of laughter simply by doing an
accurate imitation of Perot's Dumbo ears, jerky movements, and piercing Texas drawl; they didn't even need to caricature him, because
the man himself was a walking caricature. He would've made a strange President, that's for sure.)